#!/usr/bin/env python
# encoding: utf-8
#
# This file is part of BeRTOS.
#
# Bertos is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#
# As a special exception, you may use this file as part of a free software
# library without restriction.  Specifically, if other files instantiate
# templates or use macros or inline functions from this file, or you compile
# this file and link it with other files to produce an executable, this
# file does not by itself cause the resulting executable to be covered by
# the GNU General Public License.  This exception does not however
# invalidate any other reasons why the executable file might be covered by
# the GNU General Public License.
#
# Copyright 2008 Develer S.r.l. (http://www.develer.com/)
#
#
# Author: Lorenzo Berni <duplo@develer.com>
#

import sys

if sys.version_info < (2, 6, 0):
    from os.path import *
    def _posix_relpath(path, start="."):
        """Return a relative version of a path"""

        if not path:
            raise ValueError("no path specified")

        start_list = abspath(start).split(sep)
        path_list = abspath(path).split(sep)

        # Work out how much of the filepath is shared by start and path.
        i = len(commonprefix([start_list, path_list]))

        rel_list = [pardir] * (len(start_list)-i) + path_list[i:]
        if not rel_list:
            return curdir
        return join(*rel_list)

    def _nt_relpath(path, start="."):
        """Return a relative version of a path"""

        if not path:
            raise ValueError("no path specified")
        start_list = abspath(start).split(sep)
        path_list = abspath(path).split(sep)
        if start_list[0].lower() != path_list[0].lower():
            unc_path, rest = splitunc(path)
            unc_start, rest = splitunc(start)
            if bool(unc_path) ^ bool(unc_start):
                raise ValueError("Cannot mix UNC and non-UNC paths (%s and %s)"
                                                                    % (path, start))
            else:
                raise ValueError("path is on drive %s, start on drive %s"
                                                    % (path_list[0], start_list[0]))
        # Work out how much of the filepath is shared by start and path.
        for i in range(min(len(start_list), len(path_list))):
            if start_list[i].lower() != path_list[i].lower():
                break
        else:
            i += 1

        rel_list = [pardir] * (len(start_list)-i) + path_list[i:]
        if not rel_list:
            return curdir
        return join(*rel_list)

    import posixpath
    posixpath.relpath = _posix_relpath
    import ntpath
    ntpath.relpath = _nt_relpath
from os.path import relpath
